I use Linux as my native OS at my current shop and thought "Well they use Skype for Business and there's a new Skype for Linux client" .. but nope. Just as stated in this thread, it's a totally different protocol that's part of their Lync product.

I ended up getting a license for Sky, a 3rd party commercial Skype for Business client for Linux. It's pretty decent for what it is, but I could have just installed a Windows VM, used VNC, shared the VNC session and gotten the same thing.